Oracle__12. Oracle 1Z0-051 Exam - Sequence Objects

Question 1

What is returned by this statement? CREATE SEQUENCE seq1 START WITH 100 INCREMENT BY 10 MAXVALUE 200 CYCLE NOCACHE; SELECT seq1.nextval FROM dual

Answer 1

1The first statement creates the sequence but does not have the MINVALUE so the sequences starts as 1

Question 2

Can a Sequence Object be referenced in a CHECK constraint at a column level or table level?

Answer 2

Neither.A Sequence object cannot be used as a constraint

Question 3

Can a Sequence Object be referenced in a DEFAULT value?

Answer 3

No

Question 4

What keyword from a SEQUENCE object refers to the last sequence number that has been generated?

Answer 4

CURRVAL

Question 5

Are numbers generated from a sequence object only available for one table?

Answer 5

No.Sequence number are available to multiple tables or queries.

Question 6

What happens when the sequence object reached the MAXVALUE.

Answer 6

an additional request for a NEXTVAL will receive an error

Question 7

What statement can be used to increase the maximum value of a Sequence object?

Answer 7

ALTER SEQUENCE sequencename MAXVALUE newvalue

Question 8

What happens with sequence number if any are used in a transaction and the transactions is rolled back?

Answer 8

They are lost.

Question 9

What is the syntax to remove a sequence object from a database?

Answer 9

DROP SEQUENCE sequencename

Question 10

What happens to a Sequence object when a table is dropped?

Answer 10

Nothing

Question 11

What is the default minimum value of an ascending Sequence?

Answer 11

1

Question 12

What is the default sequence value of an ascending Sequence?

Answer 12

1

Question 13

What two references are used to retrieve information from a Sequence object?

Answer 13

1. NEXTVAL2. CURRVAL

Question 14

What 3 clauses can use a NEXTVAL or CURRVAL?

Answer 14

1. SELECT2. VALUES of an INSERT3. SET of an UPDATE

Question 15

What keyword added to a SELECT statement does not allow NEXTVAL or CURRVAL?

Answer 15

DISTINCT

Question 16

Can a NEXTVAL or CURRVAL be used as a DEFAULT value in a CREATE statement?

Answer 16

No

Question 17

What clause added to a select statement does not allow NEXTVAL or CURRVAL?

Answer 17

GROUP BY

Question 18

Can NEXTVAL or CURRVAL be used in a Subquery?

Answer 18

No

Question 19

What 3 instances can a sequence have a gap in the numbers?

Answer 19

1. roll back2. system crash3. same sequence is used on multiple tables

Question 20

How many values will oracle cache for a Sequence object?

Answer 20

20 values

Question 21

What is the primary use of the SEQUENCE object?

Answer 21

Primary keys

Question 22

What keyword in the CREATE SEQUENCE statement is not recommended if the Sequence is used for Primary keys?

Answer 22

CYCLE

Question 23

Between CYCLE and NOCYCLE what is the default value when creating a Sequence?

Answer 23

NOCYCLE

Question 24

What happens when a sequence reaches the MAXVALUE and the CYCLE values is set?

Answer 24

The sequence restarts at the MINVALUE

Question 25

The CYCLE and NOCYCLE are keyword for which database object?

Answer 25

SEQUENCE

Question 26

What happens to a sequence when the NEXTVAL reaches the MAXVALUE and the CYCLE option is specified?

Answer 26

The NEXTVAL becomes the MINVALUE